Selector system for amplifiers



June 9,1942. C, A, HEILAND I 2,286,170

SELECTOR SYSTEM FOR AMPLIFIERS Filed July 26, 193'? 2 Sheets-Sheet lHPM/6 Checa/r June 9, 1942. c. A. HEILAND SELECTOR SYSTEM FOR AMPLIFIERSFiled July 26, 1937 2 Sheets-Sheet 2 W r MW wf@ 7 W www n -V 6# 6 :my ww w w -u w T ,.y mmv 1. L W Q l W iwm.. m ma.. 8 6 wl f www .www 4 W MPatented June 9, 1942 2,280,110 d y n. ssmcronsysram ron ammassi Cari A.Heiland. Denver, Colo.,

assigner-to Heiland Research Corporation, Denver, Colo.. a eorporaa c Ytion of Colorad Applicaties my ze. naar. sensi No. 155,71? scisma(cime-sse) 'I'he controlling device is useful in any circuit to which aseries of impulses pass in a more or less definite timed relation. Itschiel use is probably in connection with an amplifying system foramplifying a series of electrical impulses. By use ofthe device with anamplifying system; the degree of ampliiication which is given to eachimpulse may be controlled in such a manner that certain of the impulseswillvbe amplified to the full power of the amplifying system. whileothers will be amplified to a lesser extent, or entirely prevented frompassing completely through 'the system.

One particular field of use to whichA the inthat of geophysical `exofthe received signals decreases.

Y In seismic exploration there is an additional diiiiculty encountered.When a charge of dynamite or "shot" is. energy received by xed distancesfrom rst of waves which the shot point will consist have traveled at ornear the f. :L .f near the surface. The times at which the reected wavesarrivewill be proportional to the depths of the surfaces reiiectingthem.` In both electrical and seismic work it frequently occurs thatcertain eil'ects are recorded tired near the surface, 'thei a number otdetectors atl at undesirable times and such effects, on account of theirmagnitude, sometimes obscure or interi'ersI with subsequent or precedingimpulses on which the interpretation must be based. In electrical workthese effects may be'the result ot conducting bodies, phidesfor saltwater beds 4or iissures without structural signicance orzinterest. Inseismic work the undesirable eiiectsmay be due to the surface waves orto reflections from strata.4 er bodies having no commercial interest or'signincance. t c

One use for the'present invention is vthe elimination of suchundesirable eiiects from the record of the receipt of the energyimpulses.

Ordinarily the tection of which the exploration is not concerned, or maybe readily determined, and their depth iixed, with suiilcient, accuracyto render theirelimination possible.

The primary object of the invention is to provide la novel form ofcontrolling device for an electric circuit through` whichI a series oiimpulses pass in a certain timed sequence, whereby .necting with thecircuit a second `circuit so arranged that when the second-circuit isclosed. the passage of electric .current through the first circuit willbe interfered with. A light sensitive cell is interposed in the secondcircuit. and means are provided whereby light is supplied to the lightsensitive cell in intensities .that vary in a predetermined manner andin* timed relation to the impulses passing throughcthe iirst circuit.y

Another object of the invention is to provide a novel device forcontrolling,l the light falling upon a light sensitive cell and varyingthe intensity of the lightin a predetermined manner and at predeterminedtimed intervals.

To control the operation of a light sensitive cell a series ofadjustable shutters is passed through the light beam falling upon thecell. in such a manner that each shutter intercepts a certain portion ofthe light beam. The shutters are ycarried through the beam at a`determined rate of speed so that by a suitable adiustment of eachshutter the vamount of'light reaching the cell at any given instantpredetermined fashion.

In the accompanying drawings: t Figure l is a perspective view of oneembodiment yoi! the invention. v v i Figure 2 is a perspective view ot amodimay be controlled in a auch as disseminated sulexistencel'ofbodies.in the dec ure 1, a light sensitive cell current -which ranism-beingcontained in a case `I9 connects the frame I3'and stance an :is shown.Inasmuch as it is a perspective view oi'. a modiflform of embodimentshown in Figure '1 is a detail elevation showing an elec-l trical clutchfor starting the device.y

Figure 8 is a diagrammatic view of an elecn trical control system.

Describing the drawings more particularly, and y considering first theembodiment shown in Figmounted upon a hase 8 on a vertically disposedsupport 9. Horizontally'spaced fromv the cell v1 is'a light source atIII. arranged to throw a beam of light upon to flow through thecircuitwires I2.

rn order to vary the animator-light "mining upon the cell 1,and-consequently tovary the l is permitted to vpass through the cell andthe circuit, a vertically movable frame I3 -Is vinterposed between thelight source III and the cell 1. The frame I3 has a central opening I4for the lpasage of the light beam, and means are provided forobstructing portions of the opening I4 so that a portion of .the lightbeam will be vintercepted and prevented from reaching the cell 1.Advantageously these means may take the form of shutters I5.

In'the embodiment shown in Figure l, one of the side members of theframe I3 is provided with a longtiudinally extending slet I8, and theshuttersY I5, which are in the form of long, rectangular, and narrowstrips, are slidably mounted in side-by-siderelation in the slot. Theportion ofthe light beam which is intercepted by each ofthe shutters maybe easily adjusted by moving the individual shutters inwardly orloutwardly. with respect tothe frame. A 'typical arrangement is shownvvin Figure 1, where it will be seen that as 'the frame travelsdownwardly, at first the amount of light reaching the cellwill beincreased, then decreased, and finally A.increased again.V

' The movement ofr the frame I3 maybe controlled by a drum l1 that volveat constant speed by a clock-work escapement or other, synchronous`-mechanism for rotating the drum at a constant speed, such mech- I8; Acord drumv I1.V

In order to control theV 'releaseof able catch device may be provided.In this inelectro-magnetically* voperated stop 20, adapted to. engagethe bottomof'the frame,

the operation of the device in synchronism with the impulsesv whosepassage through a circuit is vto be controlled, theoperation-of thereleasing device 20,15

mic exploration system, would be connected with the shot-ming systern insuch a manner as to release the vcatch atthe instant of iiring the shot.

The speed of the descent of the frame I3 is regulatedby the mechanismwithin' the casing is illustrated'at 1,'

the cell 1 'to allow-current is allowed -to rethe" frame I3 to begin itsdownward motion, any. suitpreferably synchronized with Athe operation ofsuch circuit. Thus in a seisthe magnetic catch 2l)v I8, so vthat thetime interval which has elapsed when any certain one of the shutters Ireaches the light beam, is denitely xed, and therefore, by thelongitudinal sliding adjustment of each of the shutters in the slot, theamount of light reaching the cell 1, and consequently the amount ofcurrent flow in the circuit, at any given instant may be controlled. Asatisfactory speed in relation to the width of the shutters is such thatthe passage of each shutter through the beam requires one-tenth of asecond. Therefore if it is desired to create a certain current flowthrough the circuit I2 one second after the beginning of the, operation,the tenth shutter from the beginning will be adjusted to pass siredcurrent to flow through the cell.

ment shown l'in Figure ly is illustrated. In this embodiment theshutters 2I are supported in a `stationary frame= 22 having an opening23,

into which the shuttersl may be projected the desired distance. A lightsensitive cell 24 --is supported upon one side ofthe frame 22 on amovable carriage 25, and a source of light is 1 supported uponthefcarriage 25 on the opposite side ci the frame in such a manner as tocast aA beam` of light upon the cell 24' opening 23. The carriage 25 maybe moved longitudinally of the frame 22 by suitable means, shown inFigure 2. es a threaded shaft 26 running parallel tol and members of theframe 22 and passing through a threaded opening 21 inthe carriage.

for driving the shaft 26 may beenclosed in the casing 28, and anelectrical clutch between the shaft and the motor to control therotation of the shaft 26. The shaft 26, being revolved at a constantspeed, the carriage 25 moves ata constant speed past the shutters 2Iwhich intercept varying portions of the light beam thrown by they lightsourceupon'the cell 24. The clutch may circuit. f

InFigure 3, an embodiment is disclosed which is advantageous forvusewhere high speeds are required.v Inthis embodiment, a rotatable shaft-29 is verticallydisposed, and carries a disk supso'port 30. The seriesof shutters II may be adjustably mounted about theuperiphery of thedisk- 30 in any suitable manner, provided that they are longitudinallyadjustable in .a verticaldirection. A light sensitive cell 55 adjacentthe periphery of the suppOltlngdisk 30 in such a position that theshutters 3l may pass between itanda light source, as at 33.'.

To drive .the .shaft 29 and disk 30, a spring I 34 may be connected tothe shaft, and an electromagnetic releasing device 3.'i may be `employedto engage the disk to preventits rotation until the magnetic device isreleased'. L

. In Figure 4 a modification of the embodiment ,as shown in Figure 3 isillustrated. ,In this form 55 the series of shutters 36 .is stationary,being adjustably mounted upon a support 31. -A swinging arm 3B,driven-by a motor enclosed in a casing 39, carries the light sensitivecell 40 and ,I source of light 4I. As thef'arms swing from one end ofthe series of Vshutters to the other, the shutters will, due to thevarying amounts which they project rupwardly between the cell and sourceof light, intercept the light beam, and permit varying intensitiessufficient lightto the cell 1 vto permit the de through the q above thelongitudinal A continuously running synchronous motor 26a interposed beoperated by the firing Y 32is mounted different portions of aesaivo and,through the primary 41 of an audio frequency transformer, to thepositive terminal of a B battery. The plate 48 of the triode is alsoconnected through the resistor 46 to the plate 42 of the amplifyingtube. The cathode 49 of the triode is grounded and is connected throughthe bias battery 50 and resistor 5| and to the cathode of the phototube.

The operation of this circuit is as follows: When no light is fallingupon the light sensitive cell 45 the operation of the plate circuitconnected with the plate 42 is not interfered with, and all of theimpulses passing through the plate circuit are amplined to the fullpower of the system: When, however, light falls on the light sensitivecell, a positive charge from the B batto the grid, v

tery is built up on the grid 43, the strength of this charge dependingupon the amount of light falling on the cell. As the positive charge onthe grid 43 increases, the conductance of the triode 44 increases and aproportional amount of the current from the plate circuit of theamplifying system is bypassed to the ground. vThe amount of current sobypassed is proportional to the amount of light falling upon thelightsensitive cell, and therefore, as the passage of the current flowswhen no light falls on the cell 51. When a beam of light, the size ofwhich is controlled by the adjustment of the shutters that pass throughit strikes the cell 51, proportional voltages are produced across theresistors 59 in the plate circuit. The grid controlling the platecurrent flow in an amplifying tube, in this case, a second control grid53 of the pentode 52 and the cathode 60 through the grounds 6I, are tiedinto the plate circuit of the triode in such a manner that theirrelative potentials are varied in proportion. to the light falling onthe light sensitive cell 51. By the `battery and potentiometerarrangement shown in Figuren, at 62, the second control grid is sobiased that no plate current flows through the pentode when the lightsensitive cell receives no light. In other words. when no light falls onthe light sensitive cell, the grid 53 becomes negatively charged. Whenthe light sensitive cell receives the maximum amount of light, themaximum amplification by the pentode occurs.

The circuit shown in Figures 5 and 6 illustrate examples of circuitsthat may be used with the light sensitive cell and its control forvarying the light beam falling thereon. Many other arrangements ofcircuitsand of various types of vacuum tubes may be employed.

Figures 7 and 8 disclose an operating larrangement for thecontrol of themoving portion of the device. Such a system may be used with any of thediilerent forms shown, although it is illustrated as embodied in theform disclosed in Fig- `ure '2. In this arrangement, instead of aclockshutters through the light beam is timed with relation to theimpulses, the adjustment of a shutter passing through the light beam atthe time of passage through the amplifying circuit of any given impulse,determines the degree of amplification of that impulse.

When any `of the photoelectric cell controls disclosed in Figures 1-4inclusive is applied to the cell 45, the positive charge upon the grid43 work or spring motor controlled .by an electric release, a constantlyrunning motor is used with an electric clutch for clutching the motor tothe shaft at the instant that it is desired t0 set the device inoperation. The motor is preferably of varies according to the amount ofthe light beam ,f

which is intercepted by the shutter, which at that instant is passingbetween the light source and the cell. As the passage of the shuttersthrough the light beam is synchronized withg'the impulses of the platecurrent from the plate 42, the setting of the shutters determineswhether that impulse shall be bypassed to the ground, whether it shallpass to the primary 41 in undiminished condition, or whether it will bemerely weakened and passed to the primary. For

example, with the shutter arrangement shown in Figure 1, if the travelof the frame I3 is started at the shot instant of a seismic system, thefirst impulse to reach the receiving station, which will be the surfacewaves, will be eliminated from the record, because a substantial amountof light is` permitted to reach the cell, and this light causes theoperation of the circuit to bypass the impulses in question. s

In Figure 6, another system is` shown f or making use of the lightsensitive cell control. In this system, instead of bypassing certain ofthe impulses tothe ground, use-.vis made of a pentode 52 having a secondcontrolgrid 53. The `signal current is led to the grid 54. "I

In thiscase also a triode 55gis employed, such triode having a grid 56connected through a light the running motor *out departing from thespirit or sacrificing any ,f

the type that runs at a constant speed in order that the speed of travelof the moving part of the device may be at avdeflnite rate.

In Figure 7 the shaft of a motor is designated 65 and the driving shaftof the selector device 66. The adjacent ends of the shafts 65 and 66carry `driving and driven elements 61 and 58, rey spectively, of anelectrically operated clutch of suitable design.l The operation of theclutch is controlled through circuit wires 89 qnnected through a slipring 1li to a magnetic device 1l in such manner that when the circuitisclosed, the clutch members will be engaged, and'the shaft 66 started.Obviously any of the various embodiments may be,` constructed with sucha driving ar-i rangement.

In Figure 8 a desirable circuit is illustrated for the control of theclutch. The circuit includes l an electrical nring device for theexplosive charge 12 that is used for settingup the waves-to be recorded,the clutch magnet 1|, and a switch 13. Upon closing the switch 13, thecharge .12 will be exploded, and the shaft 66 will be connected to 14,setting the selector device inoperation. ,f

From the foregoing, it is thought that the construction, operation andmany advantages'of the herein described invention will be apparent tothoseskilled in the art without'further description, and it will beunderstood that various changes in the size, shape, proportion and minorl` details of construction may be resorted to withof the advantages ofthe 1. In a geophysical prospecting system that ininvention.

connected with the transmitting circuit' and arranged to attenuatesignals `transmitted by the said transmitting circuit to an amplitudeinsufficient to operate the recorder when the said secwaves, said meanscomprising a second circuit ond circuit is energized, a time-controlledmechanism for energizing the said second circuit at intervalsinpredetermined sequence, and means for setting the said time-controlledmechanism in operation in synchronism with the arrival of waves at thedetector. v

2. In a seismic prospecting system including an electrically actuateddevice for propagating waves in the earth, a pickup device fortransforxrilnik auch waves to electrical impulses, a translating devicefor translating such impulses to intelligible signals, and atransmitting circuit put connected' with the pickup and an outputconnected with the translating device for passage of the electricalimpulses, means for diminishing the effect upon the translating deviceof impulses due to insignificant waves arriving at the pickup device inpredetermined sequence after actuation of the wave-propagating device,said means comprising a second circuit connected with the transmittingcircuit between the input and the output thereof and arranged todecrease the intensity of impulses delivered by the transmitting circuitat its output when said second circuit is energized, and meansconnec`ted with and set in operation by actuation of the wavepropagatingdevice for energizing the second circuit lin predetermined sequence andsynchronously with the `passage in the transmitting circuit of Yimpulses due to the insignificant waves.

having an in- 3. Means for' diminishing the effect of insignificantwaves in accordance with claim 2, wherein the means for energizing thesecond circuit comprise a light-sensitive cell, a light source arrangedto cast a beam upon said cell, and set in operation by the actuation ofthe wave-propagating device to vary in predetermined sequence theintensity oi the light beam falling upon the cell.

4. In a seismic prospecting system including an electrically operateddevice for propagating waves in the earth, a pickup device fortransforming such waves to electrical impulses. a translating,

device for translating such impulses to intelligible signals, and atransmitting circuit having an input connected with the pickup and anoutput connected with the translating device for passage of thevelectrical impulses, means for diminishing the effect upon thetranslating device of impulses due to insignificant waves arriving atthe pickup device in known sequence following actuation of thewave-propagating device, said means comprising a second circuitconnected with the transmitting circuit between the input and outputthereof and arranged to decrease the amplitude of impulses delivered tothe'transmitting circuit at its output to the translating device whenthe said second circuit is energized, and means for controllingenergization of the second circuit, said means comprising alight-sensitive cell interrupting the second circuit, a light sourcearranged to cast a beam upon the light-sensitive cell, a series ofshutters movable across the beam tohcontroi passage of the beam to thecell, the shutters being adjustable to intercept selected parts of thebeam to permit predetermination of the operation of the cell, and meansoperated-by the actuation of the wave-propagating device for setting theseries of shutters in motion across the beam.

5. Means iormdiminishin'g the effect upon the translating device ofimpulses due to insignificant waves in accordance with claim 4, whereina movable carriagev supports the shutters that form the series, saidshuttersl being adjustable thereon to vary-the portionot the beam thatthey respectively intercept, 'and wherein means controlled by operationof vthe wave-propagating device initiates movement of the carriage.

8. Means for diminishing the effect upon the translating device ofimpulses due to insignificant waves in accordance with .claim 4, whereina constant speed, continuously running 'motor is arranged for moving theseries of shutters through the beam. an electrically operated clutch isinterposedbetween the motor and the series of shut- Aters, said clutchbeing operatively connected with the wave-propagating taneous operation.

'7. Means for diminishing the eect upon the translating device ofimpulses due to insignificant device for simulwaves in accordance withclaim 4, wherein the second circuit includes a triade having its gridconnected with a source of positive charge through the light-sensitivecell, said circuitv being arranged to decrease the amplitude o!electrical impulses transmitted by the-transmitting circuit when currentis flowing` between the cathode and anode of the said triode.` n

8. Means for diminishing'the eifect upon the translating device ofimpulses due to insignificant waves in accordance with claim 4,wherein'the second circuit comprisesa by-pass including a triode havinga grounded cathode,an anode connected with the transmitting circuit, anda grid connected through the light-sensitive cell with a source ofpositive charge. i

9. Means for diminishing the effect upon the translating'device ofimpulses due to insignincant waves in accordance with claim 4, whereinthe transmitting circuit includes an amplifier tube having an anode andcathode. an input grid, and a device for suppressing the effect of thegrid, the second circuit being connected with the gridsuppressingdevice. and said suppressing device oprating upon energization of'saidsecond circu CARL s. narrano.

